WSOD when using settings to limit sources to recipes

Working on this. It's even easier to reproduce than the IS, just go to /admin/modules/browse/asdf. It doesn't just matter if it's enabled/disabled, it's also whether it exists at all.

We really need this in Drupal CMS as soon as possible.

For some reason, this MR causes a regression on 10.4.x

For example, running \Drupal\Tests\project_browser\Functional\InstallerControllerTest::testCoreModuleActivate() now gets this error on activation:

{"message":"PluginNotFoundException: The \u0022filter_format\u0022 entity type does not exist.","phase":"project install"}

I'm sure the reason will be obvious once it's tracked down, but wow that's a weird bug right now.

🐛 Fix fallback logic for empty $source in browse() method to ensure config validation with improved fallback logic Active

Yes, that is an alternate approach to fixing the same bug.

I've left a couple of comments in the MR hoping that they could be included as well. But leaving at NR just in case you don't want to cover those as well.

+1 to RTBC for all of the tweaks since my initial fix. That installer decorator change being the needed fix is wild. I was half-wrong in #7, not obvious at all!

Manually tested this per the Steps to reproduce in the issue summary. The WSOD is replaced by a 404 error. Also tried @tim.plunkett's steps in comment #2. With the MR is applied, the WSOD also gone.

Look at the code and discussions in GitLab. Checked in with @phenaproxima in Slack. He confirmed the discussion about plugin decoration is outside the scope for the current issue.

Looks good to me.

tim.plunkett → credited chrisfromredfin → .

Interestingly enough, I was messing around with higher levels of PHPStan and Level 4 would have caught at least the part from 🐛 $source !== 'recipes' is a comparison of incompatible types Active

Done!